When it comes to fully understanding 3D integration processes, Sarah-Lyle Dampoux (my tour companion from Loomis Group) and I came to the conclusion that there’s really nothing like live, hands-on demonstrations to really drive home these technologies. During our visit to Leti, the CEA laboratory located on the Minatec campus in Grenoble, France, we received a royal welcome and a grand tour of the campus that is so vast, there is a common fleet of bicycles available for staff to get from one location to another.
Once we were suited up in full clean room attire, we headed off to the facility where advanced CMOS where much of the work on high density TSV integration is done, as well as the mid-density TSV protyping area. During the tour, we got to do things like: initiate a direct wafer-to-wafer bond, see actual TSVs that had been manufactured using a via last approach (sure beats an SEM photo), witness both the copper-to-copper thermocompression bond process in an EV Group bonder as well as the EVG/Brewer Science temporary bond/debond process as its being fine-tuned in Leti’s labs. We also got a close-up look at Leti’s 3D wafer-level packaging projects. My excitement was similar to my childhood visit to FAO Schwartz toy store in New York City.
The common denominator of all the companies being visited on this tour de France is Leti. As I mentioned yesterday, Both Soitec’s core competencies, Smart Cut and Smart Stacking, were developed by Leti scientists. While not an offshoot of Leti, Alchimer has collaborated in projects with them. SET/Replisaurus and Leti are involved in a common lab agreement to develop Replisaurus masters for the start-up’s electrochemical pattern replication process (ECPR); and in its previous incarnation as Alcatel Micro Machining Systems, Tegal Europe partnered with Leti to develop industrial process capability in DRIE and LTPECVD for 3-D interconnect applications. 
In fact, as I toured through the facility, I noticed that pretty much every equipment manufacturer you can think of has a presence in Leti’s industrial level production cleanrooms; Applied Materials, Lam Research, Semitool, S.E.T, Surface Technology Systems, and low and behold, SUSS Microsystems AND EV Group tools sitting side by side in peaceful coexistence.
As Leti’s mission is to generate innovation and transfer the technology to the industry, much of the development work beyond proof of concept is carried out in this production setting, the idea being that ramp to production is much quicker. So this was as close to the action as I’ve ever been. I’ve seen lots of tools being developed and demoed, but seeing an industrial operation really illustrated the magnitude of these processes and operations. Nothing went unnoticed, from the deliberate method of suiting up (for example I kept putting my bootied foot down on the wrong side of the divider and had to start over again) to experiencing the claustrophobic feeling of being completely covered from head-to-toe, only eyes exposed. After a few hours in this costume, I wondered how people manage not only to work full days this way, but also carry out critical evaluations. I was beyond impressed.
And let’s not forget social event of the day. Hosted by Leti CEO, Laurent Malier, the guest list included Claude Massit, head of heterogeneous integration on silicon; Andre Rouzaud; deputy manager of heterogeneous integration on silicon, Mark Scannel, business development 3D integration technology; Nicolas Sillon, lab manager; David Henry, Laurent Clevalier; Cyrille Laviron, project manager, Replisaurus collaboration; Marc Aid; Mike Thompson, CTO Replisaurus; Alan Cuthbertson, Replisaurus/Leti common lab manager; Guido Groet, CFO Replisaurus; Mikael Fredenberg, co-founder, Replisaurus. True to French hospitality, our mid-day meal — a four-course, 2 hour event complete with wine — was thoroughly enjoyed by all (see what I mean by royal welcome?). I was truly honored to have been surrounded by such an assembly of genius. Thanks everyone – and especially our tour guides for the day, Nicolas Sillon and Andre Rouzaud – the visit went beyond my expectations. — F.v.T.
